Recently, a three-dimensional integration technology of laminating the same or different types of semiconductor devices has attracted attention with respect to high integration of a semiconductor device. In such a three-dimensional integration technology, a technology of joining junction surfaces of substrates together to which conductive materials formed of an electrode or wiring and insulating materials are exposed, is important. In general, bonding at room temperature is known as a bonding technology of two substrates. The bonding method at room temperature is a technology of performing bonding by activating surfaces of two substrates to be joined together in a vacuum atmosphere, and by performing pressure-welding with respect to the activated surfaces. In the bonding method at room temperature, it is possible to directly join the bonded materials (the substrates) together without requiring a heat treatment. For this reason, there is an advantage in that it is possible to suppress deformation such as expansion of the substrate according to the heat treatment, and to accurately align two substrates at the time of performing bonding.
However, in the bonding method at room temperature described above, it is possible to directly bond metals as the conductive material together, but it is not possible to directly bond oxide films, nitride films, or the like together, which are generally used as the insulating material. For this reason, in the related art, a bonding method at room temperature is proposed in which it is possible to simultaneously bond conductive materials and insulating materials together by using a trace metal which is attached onto a bonded surface (hybrid bonding) (for example, refer to Patent Literature 1).